102 Rhamnee—Rhaninus. 
nally. Flowers often small and green, rarely blue, yellow, or 
white as in Ceanothus. Calyx small, tube coriaceous, with 4 
or 5 valvate lobes. Petals concave, often on long slender 
claws. Stamens equalling and opposite the petals. Fruit 
various. There are 37 genera and about 430 species of 
this order, from the warmer and tropical regions of the whole 
world. 
Palitirus aculeatus—a branching spiny shrub with small 
3-nerved leaves, minute flowers, and curious dry fruits in which 
the disk is enlarged, forming a circular wing—is sometimes cul- 
tivated as a curiosity under the name of Christ’s Thorn; and 
two or three species of the curious South American genus 
Collétia are occasionally met with in collections. They are 
leafless spiny shrubs, some of them with remarkably thickened 
and flattened branches, and small white or yellowish flowers. 
1. RHAMNUS. 
Evergreen or deciduous shrubs. Flowers in axillary cymes, 
often unisexual. Petalssometimes wanting. Disk coating the 
calyx-tube. Fruit a drupe, with 2 to 4 hard-shelled 1-seeded 
stones. A genus of sixty species, found in nearly all temperate 
aud tropical countries except Australia. The name is said to 
be of Celtie origin, signifying a tuft of branches. There are 
two indigenous deciduous species: one, R. cathdarticus, a spiny 
shrub with ovate serrate leaves; and the other, R. Frangula, 
unarmed, with obovate entire leaves; both have 3-nerved 
leaves. 
1. R. Alatérnws.—An evergreen glabrous shrub with linear 
or ovate-lanceolate serrate shining leaves, very variable in size, 
and apetalous flowers. There are several varieties, differing in 
the size, form, and variegation of the foliage. Itis a native of 
the South of Europe. A. latifolius is merely a variety of this. 
2. CEANOTHUS. 
Evergreen shrubs with alternate or rarely opposite petio- 
late leaves. Flowers small but numerous, in terminally thyrsoid 
cymes or panicles, blue, white or yellow. Fruit a 3-lobed drupe, 
splitting from the axis, and opening along the inner edge. 
Twenty-eight species have been described, all from North 
America, chiefly from the western coast. They are rather 
tender, and will only bear our winters in the south and west 
or against a wall. The name was applied to a spiny plant 
